`QuicStreamAdapter` should implement more methods of `BaseTransport`

[Jinzhou Zhang]

TLDR: At least need to implement:

• is_closing
• close

Long Story

It seems that StreamWriter returned by QuicConnectionProtocol#create_stream will cause error when GC-ed.

Here is the minimal example:

import asyncio

from aioquic.asyncio import QuicConnectionProtocol


async def tmp():
    proto = QuicConnectionProtocol(None)
    reader, writer = proto._create_stream(123)
    del writer
asyncio.run(tmp())

The following exception occurred:

Exception ignored in: <function StreamWriter.__del__ at 0x1034b5e40>
Traceback (most recent call last):
  File ".../python3.11/asyncio/streams.py", line 395, in __del__
    if not self._transport.is_closing():
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File ".../python3.11/asyncio/transports.py", line 25, in is_closing
    raise NotImplementedError
NotImplementedError:

It is called in StreamWriter#__del__:

class StreamWriter:
    ...
    def close(self):
        return self._transport.close()

    def __del__(self):
        if not self._transport.is_closing():
            self.close()

[Jeremy Lainé]

As noted in #169 i am not happy with the API, and am still considering dropping it in version 1.0

[Jinzhou Zhang]

Understand. :)